The use of radio-frequency identification (RFID) devices has started to become more widespread since applications in retail sales, product manufacturing, shipping, traffic management, and so forth, have started to materialize. In many of these applications, large numbers of RFID tags, individual integrated circuits with antenna, are embedded into products to enable the tracking of the products. With the possible exception of traffic management, the RFID tags have an inherent requirement to be inexpensive, so as to not negatively affect the cost of the products in which they are embedded.
A factor in the overall cost of an integrated circuit (IC) is the testing that is performed on the IC. In general, a complete test of an IC will cost more than a simple functional test of the same IC. Furthermore, a test that takes an extended amount of time will result in a higher testing cost since additional testing facilities may be needed to meet production requirements.
A testing technique that can permit the testing of the integrated circuits is to use probes that can be lowered onto semiconductor wafers to provide electrical connectivity between the ICs on the wafer and the test equipment. With the connection made by the probes, the tests can be performed on the ICs to determine the properly operating ICs.
A disadvantage of the prior art is that the use of probes to test the ICs has limited capability in testing the RF performance of the ICs. Therefore, an additional test (or tests) may need to be performed to ensure that RF circuitry on the ICs is operating properly. The need for additional testing will increase the overall testing time, complexity, and cost and therefore increase the overall cost of the ICs. Additionally, the use of probes to test ICs requires a high degree of precision (in order to make proper contact on the ICs with the probes). Furthermore, probes are mechanical devices that are expensive and wear out with use.